Hand-guided power-driven twowheeled portable saw



C. E. WHITTLE HAND-GUIDED POWERDRIVEN TWO-WHEELED PORTABLE 'sAw Filed Jan. 51, 1947 Sept 6, 1949.

4 Sheets-$heet 1 IN V EN TOR.

C. E. 'WHITTLE Sept 6, 1949.

HAND-GUIDED POWER-DRIVEN TWO-WHEELED PORTABLE SAW Filed Jan. 31, 1947 4 Sheets-Sheet 2 v INVENTO emf age/Mow 906M243 Sept. 6, 1949. c. E. WHlTTLE 2,480,893

HAND-GUIDED POWER-DRIVEN TWO-WHEELED PORTABLE SAW Filed Jan 31, 1947 4 Sheets-Sheet S /Q :EIE-El Z p c. E. WHITTLE 2,480,893

HAND-GUIDED POWER-DRIVEN TWO-WHEELED PORTABLE SAW Filed Jan. 51, 1947 4 sheets' sheet 4 fi /g' [a i vi 7 7 .3 W

- IN V EN TOR.

A. l tvil Patented Sept. 6, 1949 HAND GUIDED' POWERu-DRIVENHEWO WHEELED PORTABLE SAW* Charles Edgerton Whittl signor to Tidewater wick, Gaz, a partnership e, Brunswick, Gaz, as

Application-January 31, 194.7, Serial;.l\lo.-725',624.

3 Claims.

My invention relates broadly. to portable power sawsand more particularly to a compact construction of portable power saw whichmay be readily maneuvered and controlled by one-person.

One of theobjects of. my invention isto provide an improved. constructionof portable power saw which may be manufactured inexpensively on a... mass production basisior performing efiicient.

sawingoperations both.in. the felling and bucking of timber and brush.

Another. object of my. invention is .to provide. an improved construction ofpower. saw in which the frame support for. the. saw and the drivingand' adjusting mechanismv thereof .-are. dynamically balanced so. that minimum. physical. efiortis requiredin moving or. progressively. adjusting'the cutting position of thesaw.

A' further object of my invention is to provide: an arrangement 'of multiple beltd'rivenrotary power saw including a mandrel assembly for sup porting the rotary driven saw Where the mandrel" assembly may, be moved throughout a rangeof operatin positions for the felling of timber throughout a selected range of stump heights and for bucking large or small timber with selected diameter circular saw blades.

Still another object of my invention i to pro vide' a construction of power drivenportable circular sawwhich' is readily contr'ollablefrom a driving engine mounted'on a'portable chassis With means for'maintaining tension on a'multiple 'driv ing 'belt' system throughout various-position of the saw" extendingthroughout' a" range between vertical and horizontal planes.

Still another objectiofimy"invention'istofpiio vide. an improved arrangement-fliermounting a: dynamically balanced rotary 'saw with-'respecttoi ahand operated chassis wherein a mandrel-is provided for mounting the saw which mandrel is movable from a -position l substantially--below- 'the chassis to a position above :thQChfiSSiSWhHG main taininga condition-:ofidynamic balance.

Still. another. obj ect-.-ol: my; invention is to ro vide a construction oichassis,for a power driven rotary :saw havingea highv degree .of stability. in which a dynamic chassis is. .provided.with a. down.- wardly. extending. yoked'portion with respectto which. amandrelassembly may besvariably. positioned for drivingthesaw from"an enginecarried by the chassis While maintaining a conditionof stabilized equilibrium"throughouta widra'nge of positions for the saw.

Other and furtherolij ectsof fmy 'invention're sidein the improved power saw assembly and details of corrstr'uction thereof-as set forthmo're as fiuiy in the "specification hereinafter followin'g by stantially'on' line. |''l of Fig. 2 and illustrating; the saw "assembl'yiin' side elevation, showing-the maridrel'adjusted to a position in which the circularsaw isusedfor'bucking timber, that is, cuttingflledtim'ber into'desired lengths; Fig. 2is a topv plan View of the portable saw illustrated in Fig. 1;.Fig..3 is' a vertical sectionalview through th'e'porta'ble saww'iththe mandrel moved to adjust the circular. saw to a position for felling timber,' the view being taken substantially on line 3-4 of Fig.4: Fig, Us a -top plan viewiof the port able saw shown.in Fig. 3 with the circular blade. adjusted .to. timbenfelling .position; Fig. 5 is a vertical" sectional .view "taken. substantially. on line 5-5 of. Fig. .Zand .on line .5-5 'of Fig. .6; .Fig. .6 is a fragmentary longitudinal. sectional. view taken. throughthesuspension for. the mandrel; Rig. 7. issa sidetelevational view offthe adjustablesupe p0rt-for themandrel and: illlustratingparticular ly: the. relationship of the adjustable supporttotheryoke inlthev chassis of. thesawframe; Fig. ;8' is-a transverse sectional .view taken substantially on line 8-'-8- ofrFig. '7 andillustratingparticularly the 'yoke provi'ded in themhassis: of the framesupport for allowingentry of" the mandrel for maintainingistabilization of the saw -and allowing the saw t0*b*m0VBdrcl-0se :to the surface of the ground in felling operations:;fFig. 9 is a transverse-isectional-vrewthrough the mandrel support takenwsubstantially-on liner9'-9 ofFig; '7; Fig. 10;" isf'a vertical sectional iview taken substantially on line 10 40 of Fig-:4 and l B *-|Il"of 'Fig. lla'nd showing the mandrel tlow'er'ed toe :position-enter: ing :the yokd chassis-3": Fig; 11 i a; fragmentary si'delevationalv-iew of the'mandr'eliand the rela= ticn' there'of to the yoked chassis "when inthe lbwest adjusted position; the View being taken longitudinally ofth'e chassis substantially on line I'l -Wot Fig. IBTFig. 12 is a longitudinal'sec tioiial view' Iiroughthmandrel in its lowest'ad jfis'ted positioned Suustanuany line l2-I2 of Ffig13;F1"g: 13- 'is a fragmentary plan View of the end of the' a'djilstable mandrel"and showing the relaticn' therecr to the yoked'chassis with the saw adjusted to the 1ow'e s'tcuttihg position; Fig. l4'is a-sideelevatinal "viewpaitiallybrokm away and illustrated'ln sectidnshowingone of the fittings fofsupportin'g"theadjustable mandrel with re spe'ct to the chassis'off'th'efporta-blesaw andFig. 15 'isafrontview of the-fitting illustrated in Fig.

14 with a portion thereof broken away and shown in section.

Referring to the drawings in detail the chassis of the portable saw is shown constructed from tubular conduit or pipe I forming handles which may be grasped for moving theportable saw into the area where the saw is to be operated. The chassis I is suitably braced by transverse members represented at Ia, II and I2. The transverse member I2 constitutes an axle assembly supported by the wheels I3. The engine 4 has the mass thereof so distributed with respect to the chassis that the engine serves as a counterweight with respect to the balance of the mechanism and has a pendulum effect in weight distribution. This property of the apparatus of my invention has proven very advantageous as contrasted to the usual conventional practice of locating the engine in such a position above the axle that the weight requires progressively greater operating effort to control the machine as it is inclined either forward or backward from the horizontal. In my construction I provide a pair of engine suspension members 3 and I0 extending below the transverse plane of members I I-! 2. The suspension members 3 and III are slotted as represented at 3a and Ifla to allow bolts to extend through the slotted base from the engine 4 to enable the engine 4 to be adjusted longitudinally of the chassis in order to properly balance the machine, and adjust the tension on the driving belts.

A mandrel shaft I is provided for the machine of my invention in a position extending longitudinally of the chassis and off center with respect thereto. The rear end support for the mandrel shaft I is represented at 2 in the form of a substantially T-shaped fitting embracing the end of the mandrel shaft I at 2a and embracing the transversely extending member II at 21). The T- shaped fitting 2 is free to swivel about transverse member II for raising or lowering mandrel shaft I. The mandrel shaft I is provided with a curved front end portion Ia which terminates in a sleeve bearing lb disposed on an axis extending in a direction substantially normal to the longitudinal plane of the mandrel shaft I and serving as a journal for the shaft of the rotary saw blade 8. The shaft 20 carries on the end thereof a pair of driven sheaves I5 which are engaged by a pair of driving belts 9 driven from the engine sheaves it operated by engine 4.

The mandrel shaft I is supported intermediate the rear end and the front end thereof by means of a split sleeve clamp 5 which is movable to various positions within a range of travel for guidin mandrel shaft I in an orbit for selectively setting the rotary saw blade 8 in various angular positions or a vertical or a horizontal position depending upon whether the saw is to be used for bucking or felling. The blade 8 by virtue of the operation of split sleeve clamp 5 may be set vertically in a range of heights less than the fully raised position and set horizontally not necessarily in the fully lowered position as shown in Fig. 8, for example, to cut a low stump but in a somewhat elevated horizontal position to out medium stumps or fully raised to out above a swell butt or heavy turpentine face.

The split sleeve clamp 5 has the parallel extending side portions thereof fastened by bolt members I8 and I8a which pass through the side portions of the split sleeve clamp 5 and through a pair of arms 6 as shown at I8, the arms 6 being journalled on the transverse tubular member I2 constituting the axle of the machine. The transverse tubular member I2 which carries the wheels I3 is provided with a downwardly extending yoke I'I disposed permanently in the transverse tubular member I2 in a position offset from the longitudinal center line of the chassis and forming a U drop in the tubular member I2. Axle spindles I6 are inserted into the transverse tubular member I2 to serve as journals for the wheels i3. The yoke II projectin beyond the transverse limits of the transverse tubular member I2 forms flanges or limiting stops IIa and I'll) against which the arms 6 abut as shown in Fig. 8. Arms 6 may be angularly adjusted around transverse tubular member I2 on opposite sides of the yoke II. Bolt members I8 and Ilia may be loosened to permitthis adjustment and thus mandrel shaft I isrguided and controlled in a vertical plane through yoke II at the same time that mandrel shaft I may be angularly adjusted in accordance with the position in which the rotary saw 8 is to be used. When the rotary saw 8 is moved to selected position the bolt I8 may be tightened to clamp the split sleeve 5 around mandrel shaft I at the same time that arms 6 are clamped against the opposite flan es I la. and ill) of yoke II to hold the mandrel shaft 1 firmly in the selected position. Thus the fitting constituted by the split sleeve clamp 5 may be elevated or lowered to control the vertical angular position of mandrel shaft I, the split sleeve clamp 5 being slidable along mandrel shaft I as represented, for example, in Figs. 3, 4 and 10-13 to permit mandrel shaft Ito drop into U drop axle I2. That is to say, split sleeve clamp 5 has translatory movement with respect to mandrel shaft I and serves as a means for raising and lowerin mandrel shaft I at the same time that mandrel shaft I is free to twist angularly within the split sleeve clamp 5. The lower limit of the position of split sleeve clamp 5 is illustrated in Figs. 3, 4 and 10-13 while the upper limit of the position of split sleeve clamp 5 is shown in Figs. 1, 2, 5, 6, '7 and 8. Various intermediate positions of the mandrel shaft I are possible by loosening and retightening split sleeve clamp 5 with respect to mandrel shaft I.

A condition of stable equilibrium for the machine is maintained by virtue of the low center of mass secured by the mounting of engine 4 below the center of the axis of the supporting wheels I3. The equilibrium is increased as the mandrel shaft I drops into the yoke 11. When fully lowered the mandrel shaft 1 has a common center with the center line of the axle I2. The elevation of mandrel shaft I above axle I2 does not disturb the condition of equilibrium as ample counter-balance is afforded by the mass of the engine I.

The shaping of the mandrel shaft I is one of the important features of my invention where curved end Ia of mandrel shaft I serves to maintain sheave alignment between sheaves I4 and I5 for the range of the one-quarter turn drive. The curved shape of the front end of mandrel shaft I at la is very important in order to position sheaves I5 with respect to sheaves I4 to reduce wear on belts 9 and to prevent belts 9 from jumping off at sheaves I4. Fig. 3 shows the maximum twist required of the driving belts 9 in driving saw 8 from driving sheaves M to driven sheaves I 5 while maintaining constant belt tension. The T-shaped fitting 2 performs the dual function of supporting the rear end of the mandrel shaft I so that shaft I may be revolved to position the saw 8 from horizonta'lito vertical and because of the offset construction "provided by curved endla. maintain constant belt tension between sheavesfl4and"I'S'Whennnandfl sI'iaft 1 is'raiised. sheave! 4 is fixed'inelevationforeach constructioni'and sizefof'engine if" Whenfimandie'l shaft I? is raisedi'as'. in Figs? 1 and"2fthe' distance between driving sheave" I 4' and driven sheave" i5 decreases and belts 9 tend to become slack. However, fitting 2 is designed to compensate for this variation and maintain a constant distance between sheaves and [5. This is accomplished by reason of the offset construction of the T- shaped fitting 2 as shown more particularly in Figs. 6, 14 and 15.

The sleeve portion 2a of fitting 2 is connected through web with the transversely extending sleeve 2b. Sleeve 2b is journalled upon the transverse member l. The end of the mandrel shaft 1 enters sleeve 2a as a socket and has a plug 2d secured in the end of the mandrel 1 by means of transverse rivet 2e. A flange 2 which extends peripherally into abutment with the circular end of mandrel shaft 1 and the circular end of sleeve 2a is fastened in plug 211 by screw member 2g. Mandrel shaft 1 is further restricted with respect to sleeve 2a by means of flange member lb which is adjustably secured thereto by set screw 'lc thus locating the rear end of mandrel shaft 1 with respect to sleeve 2a in a manner in which mandrel shaft 1 is free to be angularly adjusted but is restricted from removal. While the confining parts are effective to maintain the position of mandrel shaft 1' so that it is free for angular adjustment as soon as released by split sleeve clamp 5, disassembly is, nevertheless, readily possible for repair, replacement of parts and routine maintenance.

In operation of the portable saw of my invention trees and brush may be felled by moving the saw under control of handle members I while the saw is being driven by the engine 4 into position for felling trees and brush as represented in Figs. 3 and 4. For bucking the logs thus felled for sawing the logs into desired lengths, the bolts [8 and lBa are loosened and mandrel shaft I raised. In moving from the lowermost position illustrated in Figs. 3 and 4 to the elevated position shown in Figs. 1 and 2 mandrel shaft 1 revolves through an angle of substantially 90. Bolts l8 and Illa are then tightened for maintaining the saw 8 in the operating position. illustrated in. Figs. 1 and 2 for bucking.

I have found the construction and arrangement of parts as described herein highly efficient in the manufacture and production of the saw of my invention and while I have described my invention in one of its preferred embodiments, I realize that modifications and changes may be made and I desire that it be understood that no limitations upon my invention are intended other than may be imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is as follows:

1. A rotary power saw, comprising a frame structure, an axle member extending transversely of said frame structure, a wheeled support for said axle member, an engine support mounted at one side of said axle member for receiving an engine adjustably thereon and serving as a counterweight for said frame structure, said axle having a U-shaped yoke therein offset from said engine support, a mandrel shaft having one end trierecn ivctaup ar se singularly mounted with respect to saidframe-structure and the shaft in said journal for rotatably "driv ing said rotarysawfor all positions of said mandrel shaft fromarempte osition housed within the U-s'h aped yoke of said' ax-l'e to a position ex teifding abtive said axle, ag-sleeve member slida bly engageable with said mandrel shaft, angularly adjustable arms extending between said axle on opposite sides of the U-shaped yoke therein and said sleeve, and means for mutually clamping said arms and sleeve in selected positions for maintaining said mandrel shaft in a selected position.

2. In a portable saw, a chassis including a transversely extending axle, a wheeled support for said axle, a frame structure depending downwardly from said chassis below said axle, an engine mounting means carried by said frame structure, an engine adjustably mounted on said engine mounting means and adjustable toward or away from said axle to form a counterweight for said chassis, a socket-like bearing depending downwardly from said frame structure in a position adjacent one side of said chassis, a mandrel shaft having one end thereof extending into said socket-like bearing and having the other end thereof curved to provide a support for a sleevelike journal, a rotary shaft journalled in said sleeve-like journal, a rotary saw carried by said shaft, means extending between said rotary shaft and said engine for driving said rotary saw throughout a range of horizontal and vertical positions of said saw extending through an angular distance of approximately a pair of arms journalled with respect to said axle and a sleevelike member slidable on said mandrel shaft and connected with said arms for maintaining said mandrel shaft in a selected position.

3. In a portable saw, a chassis including a transversely extending axle, a wheeled support for said axle, a frame structure dependingdownwardly from said chassis below said axle, an engine mounting means carried by said frame structure, an engine adjustably mounted on said engine mounting means and adjustable toward or away from said axle to form a counterweight for said chassis, said axle including a depending U-shaped yoke portion displaced from the axis of said engine mounting means, a socket-like bearing depending downwardly from said frame structure in a position adjacent one side of said chassis in longitudinal alignment with the depending U-shaped yoke in said axle, a mandrel shaft having one end thereof extending into said socket-like bearing and having the other end thereof curved to provide a support for a sleeve-like journal, a rotary shaft journalled in said sleeve-like journal, a rotary saw carried by said shaft, means extending between said rotary shaft and said engine for driving said rotary saw throughout a range of horizontal and vertical positions of said saw extending through an angular distance of approximately 90, a pair of arms journalled on said axle on opposite sides of the depending yoke therein, and a sleeve embracing said mandrel shaft and pivotally connected with the ends of said arms, said sleeve and arms being adjustable to clamp said mandrel shaft in a selected position for maintaining the plane of open.- atiun of said rotary saw.

UNITED STATES PATENTS Name Date 10 Brownlee July 18, 1944 Number FOREIGN PATENTS Country Date Sweden Oct. 16, 1909 Great Britain Jan. 23, 1919 Switzerland Apr. 16, 1920 France Jan. 25, 1927 Australia Sept. 12, 1944 

